Consolidated Statements of Income (Loss) and Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net Operating Revenues and Other
Crude Oil and Condensate	$ 1,451,410	$ 1,137,717	$ 4,326,925	$ 2,951,118
Natural Gas Liquids	180,038	112,439	480,389	299,401
Natural Gas	220,402	205,293	675,012	526,779
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts	(6,606)	5,117	64,860	(33,821)
Gathering, Processing and Marketing	784,368	532,456	2,289,702	1,351,665
Gains (Losses) on Asset Dispositions, Net	(8,202)	108,204	(33,876)	101,801
Other, Net	23,434	17,278	64,869	51,650
Total	2,644,844	2,118,504	7,867,881	5,248,593
Operating Expenses
Lease and Well	251,943	226,348	762,906	685,606
Transportation Costs	183,565	200,862	548,635	570,787
Gathering and Processing Costs	32,590	32,635	105,480	90,385
Exploration Costs	30,796	25,455	122,401	85,843
Dry Hole Costs	50	10,390	77	10,464
Impairments	53,677	177,990	325,798	322,321
Marketing Costs	793,536	552,487	2,320,671	1,373,387
Depreciation, Depletion and Amortization	846,222	899,511	2,527,642	2,690,893
General and Administrative	111,717	94,397	317,462	292,633
Taxes Other Than Income	125,912	91,909	386,319	246,068
Total	2,430,008	2,311,984	7,417,391	6,368,387
Operating Income (Loss)	214,836	(193,480)	450,490	(1,119,794)
Other Income (Expense), Net	226	(7,912)	8,349	(33,345)
Income (Loss) Before Interest Expense and Income Taxes	215,062	(201,392)	458,839	(1,153,139)
Interest Expense
Interest Expense, Net	69,082	70,858	211,010	210,356
Income (Loss) Before Income Taxes	145,980	(272,250)	247,829	(1,363,495)
Income Tax Provision (Benefit)	45,439	(82,250)	95,718	(409,161)
Net Income (Loss)	$ 100,541	$ (190,000)	$ 152,111	$ (954,334)
Net Income (Loss) Per Share
Basic	$ 0.17	$ (0.35)	$ 0.26	$ (1.74)
Diluted	0.17	(0.35)	0.26	(1.74)
Dividends Declared per Common Share	$ 0.1675	$ 0.1675	$ 0.5025	$ 0.5025
Average Number of Common Shares
Basic	574,783	547,838	574,370	547,295
Diluted	578,736	547,838	578,453	547,295
Other Comprehensive Income
Foreign Currency Translation Adjustments	$ 355	$ 141	$ 1,924	$ 8,170
Other, Net of Tax	(25)	23	(74)	68
Other Comprehensive Income	330	164	1,850	8,238
Comprehensive Income (Loss)	$ 100,871	$ (189,836)	$ 153,961	$ (946,096)